The present invention relates to a resin molding machine, in which a loader conveys a work piece from a work piece feeding unit to a press unit and an unloader conveys a molded product from the press unit to a product accommodating unit, and a resin tablet feeding machine, in which sending resin tablets by vibrating a tablet container.
Conventional resin molding machines for molding semiconductor devices will be explained with reference to FIGS. 20 and 21. In FIG. 20, the conventional resin molding machine includes: a press unit 202 having a molding die 201; a work piece feeding unit 205 feeding work pieces, e.g., lead frames, substrates, accommodated in feeding magazines 203 to a feeding table 204; a storing unit 206 storing the resin tablets; a resin tablet feeding unit 210 having a bowl feeder 207 and a linear feeder 208, which form the resin tablets in line and feed in a prescribed direction, and feeding tablet holders 209, in which the resin tablets are respectively set, to the feeding table 204; a degating unit 211 removing disused resin from molded products, which are taken out from the molding die 201; a product accommodating unit 213 having accommodating magazines 212, in which the molded products, from which the disused resin is removed, are accommodated; and a control unit 214 controlling the whole machine.
When the work pieces and the resin tablets are supplied onto the feeding table 204, they are held by a loader 215 and conveyed to the molding die 201, which has been opened. On the other hand, when the molded products are ejected from the molding die 201, they are held by an unloader 216 and conveyed to the degating unit 211. At that time, the unloader 216 cleans parting faces of the molding die 201. The unloader 216 holds and presses substrates of the molded products, and they are cooled by air so as to prevent deformation of the substrates in the degating unit 211. In the degating unit 211, the substrates are twisted to remove the disused resin, so the unloader 216 leaves the molded products, from which the disused resin is removed, and returns to take out next products. The loader 215 and the uunloader 216 are moved along a common guide rail 217, which is provided above the press unit 202. Namely, the loader 215 is reciprocatively moved between the feeding table 204 and the molding die 201; the unloader 216 is reciprocatively moved between the molding die 201 and the degating unit 211. The conventional resin molding unit was disclosed in a Japanese Patent Gazette No. 3-286817.
In FIG. 21, the conventional resin molding machine has a plurality of press units 222a-222d, which respectively have molding dies 221a-221d, and they are detachably attached to attaching sections 224 of a base unit 223 so as to change number of products and kinds of products. The base unit 233 includes: a work piece feeding unit 227 feeding work pieces, e.g., lead frames, substrates, accommodated in feeding magazines 203 to a turn table 226; a resin tablet feeding unit 230 feeding the resin tablets from tablet cassettes 228 and setting the resin tablets in a tablet holder 229; a degating unit 232 removing disused resin from molded products, which are taken out from the press units 222a-222d and held by a pick-up 231; and a product accommodating unit 234 having accommodating magazines 233, in which the molded products, from which the disused resin is removed, are accommodated.
When the work pieces and the resin tablets are supplied into the molding dies 221a-221d, they are held by a loader 236 of a loader unit 235 and conveyed to the molding dies 221a-221d, which have been opened. On the other hand, when the molded products are ejected from the molding dies 221a-221d, they are held by an unloader 237 of the loader unit 235 and conveyed to the degating unit 232. At that time, the unloader 237 cleans parting faces of the molding dies 221a-221d. The loader 236 and the unloader 237 are vertically arranged in the loader unit 235 and moved along a common guide rail 238 of the base unit 223. The loader 236 and the unloader 237 can be moved independently.
The loader 236 turns at a position xe2x80x9cOxe2x80x9d to take the work pieces from the turn table 226 and take the resin tablets from the tablet holder 229. The loader 236 is turned to head the molding dies 221a-221d, then the loader 236 is moved to a position xe2x80x9cMxe2x80x9d or xe2x80x9cNxe2x80x9d, along the guide rail 238, so as to feed the work pieces and the resin tablets to the assigned press unit. On the other hand, the unloader 237 has waited at the position xe2x80x9cMxe2x80x9d or xe2x80x9cNxe2x80x9d, then the unloader 237 takes out the ejected products from the opened dies 221a-221d of the press units 222a-222d. Further, the unloader 237 is moved to a position xe2x80x9cOxe2x80x9d along the guide rail 238, then the unloader 237 is turned to head a degating unit 232, if necessary, to transfer the products thereto. After the unloader 237 takes out the products from the opened dies 221a-221d of the press units 222a-222d, the loader 236 enters the opened dies 221a-221d instead of the unloader 237 so as to set next work pieces and next resin tablets in the molding dies 221a-221d. The conventional resin molding unit was disclosed in a Japanese Patent Gazette No. 10-58457.
These days, semiconductor devices are made compact and highly integrated with fine wires. Further, in some semiconductor devices, parts of leads are projected from a package section and connecting portions, which will be connected to terminals, e.g., bumps, solder balls, are exposed. In these cases, parting faces of a molding dies of a press unit is covered with release film, which is supplied and collected by a film unit. A conventional resin molding machine having the film unit will be explained with reference to FIGS. 22 and 23.
As shown in FIG. 22, the conventional resin molding machine includes: a press unit 242 having a molding die 241; a work piece feeding unit 245 feeding work pieces, e.g., lead frames, substrates, accommodated in feeding magazines 243 to a feeding table 244; a storing unit 246 storing the resin tablets; a resin tablet feeding unit 250 having a bowl feeder 247 and a linear feeder 248, which form the resin tablets in line and feed in a prescribed direction, and feeding tablet holders 249, in which the resin tablets are respectively set, to the feeding table 244; a degating unit 251 removing disused resin from molded products, which are taken out from the molding die 241; a product accommodating unit 253 having accommodating magazines 252, in which the molded products, from which the disused resin is removed, are accommodated; and a control unit 254 controlling the whole machine.
When the work pieces and the resin tablets are supplied onto the feeding table 244, they are held by a loader 255 and conveyed to the molding die 241, which has been opened. On the other hand, when the molded products are ejected from the molding die 241, they are held by an unloader 256 and conveyed to the degating unit 251. At that time, the unloader 256 cleans parting faces of the molding die 241. The unloader 266 holds and presses substrates of the molded products, and they are cooled by air so as to prevent deformation of the substrates in the degating unit 251. In the degating unit 251, the substrates are twisted to remove the disused resin, so the unloader 256 leaves the molded products, from which the disused resin is removed, and returns to take out next products. The loader 255 and the uunloader 256 are moved along a common guide rail 257, which is provided above the press unit 242. Namely, the loader 255 is reciprocatively moved between the feeding table 244 and the molding die 241; the unloader 256 is reciprocatively moved between the molding die 241 and the degating unit 251.
In FIG. 23, the release film 259 is supplied from the film unit 258 to cover an upper die 241a of the molding die 241. The film unit 258 is held by a fixed platen 260, to which the upper die 241a is fixed. The film unit 258 includes a film feeding section 261, which is provided on one side of the press unit 242, and a film collecting section 262, which is provided on the other side of the press unit 242 (see FIG. 22). By rotating rollers of the film feeding section 261 and the film collecting section 262, the release film 259 is sent a prescribed length from the one side of the press unit 242 to the other side thereof. The feeding direction of the release film 259 is perpendicular to the moving direction of the loader 255 and the unloader 256.
In the conventional resin molding machines, the work pieces are conveyed from the work piece feeding unit to the press unit by the loader; the molded products are conveyed from the press unit to the product accommodating unit. The work piece feeding unit includes a work piece feeding section, which sends the lead frames, the plastic substrates, etc. from the feeding magazines to the feeding table by a pusher, etc., and a tablet feeding section, which sends the tablet holders, which have holding holes corresponding to hot pitch and in which the resin tablets are set, to the feeding table. The work pieces and the resin tablets on the feeding table are held by the loader, which has waited above the feeding table. The loader conveys the work pieces and the resin tablets to the press unit, whose dies have been opened. The press unit clamps the work pieces and molds the work pieces with the resin (see FIGS. 20 and 22).
For example, a spiral vibrating parts feeder, in which a plurality of the resin tablets are stored in a bowl-shaped container and moved, with the same heading, in a spiral path by vibrating a bottom part of the container, is used as the tablet feeding section. An example of the spiral vibrating parts feeder was disclosed in a Japanese Patent Gazette No. 5-138681, in which the resin tablets are sent in order and the head of the resin tablet line is held by a hand and set in a molding die.
Another type of the tablet feeding section was disclosed in Japanese Patent Gazettes No. 6-166049 and No. 10-15994, in each of which a linear vibrating parts feeder is combined with the spiral vibrating parts feeder.
These days, semiconductor devices are made compact and highly integrated with fine wires. In QFNs (Quad Flat Non-leaded), parts of leads are projected from package sections; in BGAs (Ball Grid Array), connecting portions, which will be connected to terminals, e.g., bumps, solder balls, are exposed. Further, in some cases, a plurality of semiconductor chips are molded in one time. Preferably, in these cases, parting faces of the molding dies of the press unit is covered with release film.
In some products, heat sinks are molded together with the chips due to efficient heat radiation. In cavity down type packages, connecting faces, which will be connected to terminals, are formed, around cavities, on surfaces of substrates, so resin paths cannot be formed on the substrates. In this case, an intermediate die is detachably attached between an upper die and a lower die so as to mold with resin.
However, in the conventional resin molding machine shown in FIG. 20, the press unit 202 having the molding die 201 is enclosed by the loader 215, the unloader 216, the work piece feeding unit 205, the resin tablet feeding section 210, the degating unit 211 and the product accommodating unit 213, and a working space and an extra space are small. Therefore, it is difficult to change the arrangement of the units for wide application. Especially, the common guide rail 217 of the loader 215 and the unloader 216 is located above the molding die 201, so it is difficult to add other functional section without interfering with the guide rail 217.
In the conventional resin molding machine shown in FIG. 21, a plurality of the press units are provided. Especially, the press units 221a and 221b are enclosed by the base unit 223, the guide rail 238 and the press units 221c and 221d, so it is difficult to modify for wide application as well as the machine shown in FIG. 20.
In the conventional resin molding machine shown in FIG. 22, the press unit 242 having the molding die 241 is enclosed by the work piece feeding unit 245, the resin tablet feeding section 250, the degating unit 251, the product accommodating unit 253 and the control unit 254. With this structure, it is difficult to handle the film collecting section 262, which is located on the other side of the press unit. Further, a space for attaching and detaching the roller of the film collecting section 262 and a maintenance space thereof are small. Since the release film 259 is sent in the direction perpendicular to the direction of moving the loader 255 and the unloader 256, height of the machine must be higher, as shown in FIG. 23, so as to avoid the interference and keep a maintenance space.
Even if the loader 255 and the unloader 256 are combined and moved toward the press unit 242 from one side to form a working space around the press unit 242, conveying routes for feeding the work pieces and the resin tablets and conveying the molded products must be complex, so it is difficult to modify the machine for wide application.
To adjust amount of products and produce many kinds of products with small lot number, the press units of the resin molding machine are formed as modules, so that number of the press units can be changed. To increase number of producing the products, the loader must convey the work pieces and the resin tablets to the press unit or units at high speed. Therefore, the work pieces and the resin tablets must be transferred to the loader in a short time.
In the case of feeding the resin tablets by the spiral vibrating parts feeder only, the resin tablets are sent along a long spiral route, so that it is difficult to feed the resin tablets in a short time. Since the resin tablets are stored in the bowl-shaped container, the container needs a broad setting space. Since the resin tablets are vibrated while they are moved in the spiral route, the resin tablets contact an inner face of the container and another resin tablet, so that the resin tablets are broken, yield of the resin tablets are made lower, resin dusts are scattered and badly influences a working environment.
In the case of combining the linear vibrating parts feeder with the spiral vibrating parts feeder, vibrating directions are mutually different, so it is difficult to match feeding speed of the both parts feeders. If the feeding speed of the both parts feeders are not matched, the resin tablets are crowded, so that the resin tablets contact the inner face of the container and another resin tablet, the resin tablets are broken, and the resin dusts are scattered. Further, the two parts feeders occupy a broader space and increase manufacturing cost.
A first object of the present invention is to provide a resin molding machine capable of solving the problems of the conventional machines, executing many functions and easily expanding and modifying a structure thereof.
A second object is to provide a compact resin molding machine having enough working space and a film unit, which can be detachably attached to a press unit.
A third object is to provide a resin feeding machine capable of feeding resin tablets in a short time, decreasing manufacturing cost and an installing space.
To achieve the first object, a first basic structure of the resin molding machine comprises:
a work piece feeding unit;
a product accommodating unit;
a press unit for molding a work piece;
a loader for conveying the work piece from the work piece feeding unit to the press unit;
an unloader for taking out a molded product from the press unit;
common rail sections, on which the loader and the unloader are moved to convey the work piece and the molded product; and
an additional rail unit having a rail section, on which the loader and the unloader can be moved, the additional rail unit being detachably attached between the work piece feeding unit and the product accommodating unit, wherein the common rail sections and the rail section of the additional rail unit are disconnectably connected.
In the resin molding machine, each of the work piece feeding unit and the product accommodating unit may have the common rail section and a base section.
In the resin molding machine, the unloader, the work piece feeding unit and the product accommodating unit may respectively have sucking ducts, and
the rail section of the additional rail unit may have a sucking duct, which is capable of connecting to the sucking duct of the unloader and communicating to the sucking ducts of the work piece feeding unit and the product accommodating unit.
In the resin molding machine, the additional rail unit may have a base section, which includes a rail base supporting the rail section and a support base supporting a functional section.
In the resin molding machine, at least one of the work piece feeding unit, the product accommodating unit and the additional rail unit may include the press unit.
In the resin molding machine, at least one of the press unit may have a film unit.
In the resin molding machine, a functional section, in which a function other than a molding function is executed, may be provided at a position of the press unit.
In the resin molding machine, a resin feeding section, which feeds resin for molding to the press unit, may be provided to one of the work piece feeding unit, the product accommodating unit and the additional rail unit.
In the resin molding machine, an intermediate die feeding section, which attaches an intermediate die to and detaches the same from a place between an upper die and a lower die of the press unit, may be provided to one of the work piece feeding unit, the product accommodating unit and the additional rail unit.
In the resin molding machine, a heat sink feeding section, which feeds a heat sink to the press unit, may be provided to one of the work piece feeding unit, the product accommodating unit and the additional rail unit.
To achieve the second object, a second basic structure of the resin molding machine comprises:
a work piece feeding unit;
a product accommodating unit;
a press unit for molding a work piece;
a loader for conveying the work piece and resin for molding from the work piece feeding unit to the press unit;
an unloader for conveying a molded product from the press unit to the product accommodating unit; and
a film feeding section for feeding release film onto a parting face of the press unit, the film feeding section being provided on one side of the press unit; and
a film collecting section for collecting used release film, the film collecting section being provided on the other side of the press unit,
wherein one of the film feeding section and the film collecting section can be moved away from the press unit.
In the resin molding machine, the loader and the unloader may be moved on one of the sides of the press unit, and
one of the film feeding section and the film collecting section may be moved away from the press unit and drawn.
In the resin molding machine, one of the film feeding section and the film collecting section may be turned with respect to the press unit.
In the resin molding machine, the film feeding section may include: a film feeding roller, on which the release film is wound; and a tension roller capable of giving tension to the release film drawn from the film feeding roller, and
the film collecting section may include: a film collecting roller which winds the release film used; and a tension roller capable of giving tension to the release film collected by the film collecting roller.
In the resin molding machine, the tension rollers of the film feeding section and the film collecting section may respectively have sensors, which respectively detects revolution numbers of the tension rollers, and revolution numbers of driving sources, which respectively rotate the tension rollers, may be controlled on the basis of output signals of the sensors. With this structure, a length of feeding the release film and tension of the release film can be adjusted, so that the release film can be stably fed.
In the resin molding machine, the film feeding section and the film collecting section may respectively have guide rollers for moving the release film away from the parting face of the press unit. With this structure, the release film can be fed smoothly, and the release film is not damaged by the parting face, so that the release film can be reused.
To achieve the third object, a basic structure of the resin tablet feeding machine comprises:
a tablet sending section including a first tablet container, which forms resin tablets in line and guides them in a sending direction, and a first vibrating section, which vibrates the first tablet container so as to send the resin tablets; and
a tablet circulating section including a second tablet container, which accommodates the resin tablets which have been missed to send from the first tablet container and collected, and a second vibrating section, which vibrates the second tablet container so as to send the resin tablets to the first tablet container.
In the resin tablet feeding machine, a first conveying face of the first tablet container, on which the resin tablets are sent, and a second conveying face of the second tablet container, on which the resin tablets are circulated, may be crossed.
In the resin tablet feeding machine, the first vibrating section and the second vibrating section may respectively include linear feeders, whose vibrating directions are mutually opposite.
In the resin tablet feeding machine, a space may be formed between the first tablet container and the second tablet container, and
a dust collecting section may be provided under the space.
In the resin molding machine having the first basic structure, the additional rail unit is attached between the work piece feeding unit and the product accommodating unit, and the common rail sections and the rail section of the additional rail unit are disconnectably connected. Therefore, design of the machine can be easily expanded and modified to have many functions. If the unloader, the work piece feeding unit and the product accommodating unit respectively have sucking ducts and the rail section of the additional rail unit has the sucking duct, which is capable of connecting to the sucking duct of the unloader, the additional rail unit can be added easily.
If each of the work piece feeding unit and the product accommodating unit has the common rail section and the base section, functional sections can be changed and detached, so that the working space can be formed, many functions can be executed, layout of the machine can be easily designed for a wide use. If the additional rail unit has the base section including the rail base supporting the rail section and the support base supporting the functional section, a size of the base section can be designed on the basis of the functional section and the machine can be applied for a wide use.
In the resin molding machine having the second basic structure, one of the film feeding section and the film collecting section can be moved away from the press unit. With this structure, a space for exchanging a film roller of the film feeding section or the film collecting section can be formed, so that the film roller can be exchanged easily. If the loader and the unloader are moved on one of the sides of the press unit and the film feeding section or the film collecting section can be moved away from the press unit and drawn, the film feeding section or the film collecting section can be drawn, without interfering the rail section, in a space in which the loader and the unloader are moved, and a compact size machine can be realized. If the film feeding section or the film collecting section can be turned with respect to the press unit, a working space can be formed, so that the film roller can be easily exchanged.
If the tension rollers of the film feeding section and the film collecting section have the sensors and the revolution numbers of the driving sources, which respectively rotate the tension rollers, are controlled on the basis of the output signals of the sensors, the length of feeding the release film and the tension of the release film can be adjusted and the release film can be stably fed.
If the film feeding section and the film collecting section respectively have the guide rollers for moving the release film away from the parting face of the press unit, the release film can be fed smoothly and the release film is not damaged by the parting face. Therefore, the release film can be reused.
In the resin feeding machine of the present invention, the resin tablets in the first tablet container are formed in line and guided in the sending direction, and the resin tablets which have been missed to send from the first tablet container are accommodated in the second tablet container and returned to the first tablet container. With this structure, the resin tablets can be formed in line in a short time, speed of sending the resin tablets can be accelerated and forming resin dusts can be prevented.
If the first conveying face of the first tablet container, on which the resin tablets are sent, and the second conveying face of the second tablet container, on which the resin tablets are circulated, are crossed, good resin tablets, which can be used for molding, and bad resin tablets, which cannot be used for molding, can be properly classified.
If the first vibrating section and the second vibrating section respectively include linear feeders, whose vibrating directions are mutually opposite, vibration of the first tablet container and the second tablet container can be easily matched, so that the resin tablets can be rapidly and smoothly circulated. Further, an installing space and manufacturing cost can be reduces.
If the space is formed between the first tablet container and the second tablet container and the dust collecting section is provided under the space, the resin dusts formed by the vibration can be efficiently collected.